Generally, the occurrence of a leak should be detected at an early stage in order to limit the risks involved with the leak, especially when inflammable fluids are transported through the conduit. Furthermore, damage to environment or equipment due to leaking fluid can be limited or prevented if the leak is detected at an early stage.
In a known method to detect leakage of fluid from a pipeline, a mass balance technique is used which involves measuring the inlet and outlet flow rates, and comparing the flow rates in order to check the fluid mass balance in the pipeline.
In another known method, a statistical distribution of variations of fluid pressure or fluid flow rate during development of a leak is assumed. This method aims to detect leaks from measurements of pressure at selected intervals along the pipeline, which measurements are compared with the assumed statistical distribution. A disadvantage of the known methods is that alarms are often generated in case of no leakage, or no alarms are often generated in case of leakage, especially during varying operating conditions.